Virtual PBX system

ABSTRACT

A virtual private branch exchange (PBX) system that routes calls within a packet-switching network. Login information is received from a data device. The login information includes an alias identifying a user at the data device and a network address identifying the location of the data device on the packet-switching network. The virtual private branch exchange system associates the user&#39;s private branch exchange extension with the network address and routes calls to the user&#39;s (PBX) extension to the data device on the basis of the network address of the data device.

CROSS-REFERENCE

[0001] The present application is a continuation of U.S. patentapplication Ser. No. 10/106,524 entitled “Virtual PBX System” filed Mar.25, 2002, which is a continuation of U.S. patent application Ser. No.09/441,741 entitled “Virtual PBX System” filed Nov. 17, 1999 now U.S.Pat. No. 6,393,017, which are incorporated herein by reference in theirentireties.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates generally to a telephony system andmore specifically to a virtual private branch exchange (PBX) system fora packet-switching network (PSN).

[0004] 2. Discussion of the Background

[0005] A PBX is an automatic telephone switching system that enablesusers within an organization to place calls to each other without havingto access a public switched telephone network (PSTN). Users can alsoplace calls to outside numbers via the PBX. PBXs are typically locatedon the premises of a customer and provide a great deal of control andflexibility in the customer's communications. PBXs are well known andare described, for example in Stallings, “Data and ComputerCommunications,” 4^(th) Edition, MacMillan Publishing Co New York, 1994which is incorporated herein by reference.

[0006] One approach to implementing a PBX involves a virtual PBX callprocessing method in which a packet switching system establishes avirtual circuit between each distinct pair of user packet stations in agroup. The user packet stations exchange signaling packets via thevirtual circuits and respond to such packets by coordinating theinitiation and disconnection of voice, data, or image calls. All callprocessing, including the provision of features, such as call forwardingand automatic call back, is accomplished by the stations without the aidof the switching system. Thus, all of the intelligence of the system ison the terminal side of the system and not on the network side.Consequently, telephony agents and terminals are required to processinbound and outbound calls and perform routing. No dynamic tracking oflocations is performed by this system, and all of the terminal locationsare static.

[0007] Methods of using Internet based communication standards fortelephone communication have been developed for use with conventionalPBXs. These methods simply (1) permit remote telephone access to anexisting PBX system via a PSTN and (2) link Internet Protocol (IP)telephony clients to an existing PBX system via an H.323 gateway. H.323is an ITU (International Telecommunications Union) standard thatprovides a set of specifications for equipment and services for use withmultimedia communications over a network. An example of how IP telephonyclients are linked to an existing PBX system via an H.323 gateway isdescribed in http://quicknet.net/support/Appotes/AN00004.htm, which isincorporated herein by reference. However, such systems stillincorporate a conventional PBX, which handles call referencing andswitching.

SUMMARY OF THE INVENTION

[0008] Accordingly, one object of this invention is to provide a virtualPBX system for a packet-switching network (PSN), where the intelligenceof the virtual PBX system is located in the network rather than in theterminals.

[0009] It is another object of the present invention to provide a PBXsystem for a PSN that does not require telephony equipment.

[0010] It is yet another object of the present invention to tracklocations of users of the virtual PBX system in real time so that usersare not required to maintain static locations.

[0011] It is still yet another object of the present invention to trackusers' locations for call and message delivery each time a user connectsto the PSN.

[0012] It is still a further object of the present invention to provideconnectivity between the virtual PBX system of the present invention andexisting public switched telephone networks (PSTNs) and existing PBXsystems.

[0013] These and other objects are achieved according to the presentinvention by providing a novel method, system, computer program product,and data structure in which login information is received from a datadevice. The login information includes an alias identifying a user atthe data device and a network address identifying the location of thedata device on the PSN. The user's PBX extension is associated with thenetwork address of the data device, and calls are routed to the user'sPBX extension to the data device on the basis of the network address ofthe data device. In this manner, a virtual PBX system for a PSN isimplemented. Advantageously, the intelligence of the virtual PBX systemis located in the network instead of in the terminals (e.g. the datadevice).

[0014] Preferably, information that uniquely identifies a user is linkedto the user's PBX extension. As a result, the virtual PBX system of thepresent invention does not require conventional telephony equipment toroute calls.

[0015] The location of the user can be dynamically tracked by storingthe network address of the data device when the user logs onto the PSNwith the data device. If the user logs onto and off of the PSN withdifferent data devices, then the inventive virtual PBX system is able totrack the location of the user by dynamically storing the networkaddress of the data device that is currently connected to the PSN underthe user's alias. Cohen the user disconnects from or logs off of thePSN, the virtual PBX system disassociates the network address of thedata device that is being disconnected from the PBX extension of theuser. Preferably, the network address of the data device is an InternetProtocol (IP) address.

[0016] Additionally, known gateways provide connectivity between thevirtual PBX system of the present invention and existing PSTNs andexisting PBX systems. Thus, the virtual PBX system can complement, or beused independently of, conventional telephony networks.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] A more complete appreciation of the invention and many of theattendant advantages thereof will be readily obtained as the samebecomes better understood by reference to the following detaileddescription when considered in connection with the accompanyingdrawings, wherein:

[0018]FIG. 1 is a schematic illustration of an embodiment of a virtualPBX system that complements a standard telephony network:

[0019]FIG. 2 is a drawing of an extension aliases record for associatingeach user's alias with a group identification (ID) number and a userextension, utilized in the system of FIG. 1;

[0020]FIG. 3 is an extension locations record for associating a user'sgroup ID number, user extension, and sorting, in order of preference,various locations for each user to receive calls, utilized in the systemof FIG. 1;

[0021]FIG. 4 is a packet network locations record for dynamicallytracking and associating the group ID number, the user extension, andthe network address of users that are logged onto the virtual PBX systemof FIG. 1;

[0022]FIG. 5 is a flow chart showing how a user logs onto the virtualPBX system of FIG. 1;

[0023]FIG. 6 is a flow chart for explaining different user options thatare available with the virtual PBX system of FIG. 1:

[0024]FIGS. 7 and 8 are flow charts explaining the process for making acall from the virtual PBX system to another user via a conventional PSTNor via the virtual PBX system;

[0025]FIG. 9 is a flow chart explaining the process for receiving a callfrom an outside user with the virtual PBX system of FIG. 1; and

[0026]FIG. 10 is a schematic diagram of a general purpose computersystem that can be programmed to perform the special purpose function(s)of one of more of the devices shown in the system of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Referring now to the drawings, wherein like reference numeralsdesignate identical or corresponding parts throughout the several views,and more particularly to FIG. 1 thereof, there is shown a virtual PBXsystem 100 that interfaces with a standard telephony network 116. Thevirtual PBX system 100 includes data devices 102 and 104, apacket-switching network 106, one or more processors 108, one or moreobject storage databases 110, one or more directories 112, and one ormore databases 114.

[0028] The data devices 102 and 104 can be personal computers, palmtopcomputers, laptop computers, or any other terminal, endpoint or devicesuitable for transmitting and receiving data (e.g., voice data) over apacket-switching network (PSN). The dial devices 102 and 104 preferablyinclude microphones and speakers or other suitable equipment for sendingand receiving voice messages over the packet-switching network 106. Thedata devices 102 and 104 may also be portable devices for wirelesscommunication as with the packet-switching network 106 and for sendingand receiving voice data over a PSN.

[0029] The data device 102 includes an agent 103, and the data device104 includes an agent 105. The agents 103 and 105 are software (e.g.,Web browser software) or circuitry for allowing users to send andreceive voice packets through the data devices 102 and 104,respectively, to the packet-switching network 106. Such agents (alsocalled telephony agencies) are known. An example of an agent isMICROSOFT NETMEETING. Also, agents are described in U.S. Pat. No.5,867,494 to Krishnaswamy et al. entitled “System, Method and Article ofManufacture With Integrated Video Conferencing Billing in aCommunication System Architecture.” which is incorporated herein byreference. Preferably, the agents 103 and 105 provide a graphical userinterface for visually representing to a user various programs, files,and options for initiating and receiving calls, accessing user options.,and accessing message options, for example. User and message options aredescribed below in conjunction with FIG. 6.

[0030] The packet-switching network 106 is any suitable network forrelaying or transmitting packets, such as the Internet, a portion of theInternet, a backbone network, a local area network (LAN), or a wide areanetwork (WAN). Packet-switching networks are known and are described,for example, in Keiser and Strange, “Digital Telephony and NetworkIntegration,” 2nd ed., Chapman & Hall, New York, 1995., which isincorporated herein by reference. The packet-switching network 106connects the data devices 102 and 104 as well as the processor 108 andthe directory 112. Thus, the processor 108 and the directory 112 mayform a portion of the packet-switching network 106. The packet-switchingnetwork 106 may operate independently of a conventional PSTN or, asshown in FIG. 1, the packet-switching network 106 can be interfaced to aPSTN through a gateway such as the packet network telephony gateway 128.

[0031] The processor 108 is any device suitable for interpreting andexecuting instructions, such as a general purpose computer, a server, ordedicated circuitry. The processor may also be implemented with softwaresuch as Web server software that serves to clients (e.g., the datadevices 102 and 104) pages with information retrieved from the objectstorage database 110 and/or the directory 112, for example.

[0032] The processor 108 receives information regarding calls to be madeto and from the data devices 102 and 104. The information receivedincludes information identifying locations of users (e.g., IP addressesof the data devices 102 and 104, user's PBX extensions, and/or e-mailaddresses) and the telephone number and/or extensions of the originatorsof outgoing calls and the recipients of incoming calls.

[0033] The processor 108 and the directory 112 may be implementedseparately or on a single computer, for example. In one embodiment, asingle processor 108 is physically separate and implemented separatelyfrom multiple directories 112, with each director) 112 corresponding toa group of customers. Preferably, the groups of customers are arrangedlogically; for example, all of the users within a single company orother organization can be organized into the same group. The processor108 is configured to receive information from the packet-switchingnetwork 106 and query the directory 112 for additional information,based on the information that the processor 108 receives from thepacket-switching network 106.

[0034] The processor 108 includes, and/or communicates with, one or moreobject storage databases 110. The processor 108 may communicate with theapplication call processing (ACP) system 130 directly, as shown in FIG.1, or through a gatekeeper or other suitable device for interfacing apacket-switching-network and a conventional telephony network. Otherfunctions of the processor 108 may include, but are not limited to,controlling scripting.

[0035] receiving and processing acceptance codes (e.g., dual tonemulti-frequency (DTF) codes, discussed in U.S. Pat. No. 5,787,150, forexample), message and control handling (e.g., initiating and stoppingrecording of messages, tracking where messages are stored controllinguser options, and controlling message options), serving as a proxyserver to the directory 112, processing communications to and from theACP 130, querying the directory 112 for information, generating an alarmsignal when errors in call processing are detected, controllingredundancy if multiple directories 112 are used, and authenticatingusers who wish to gain access to the virtual PBX system 100.Additionally, the processor 108 automatically stores billing informationfor various customers, generates billing reports at specified timeintervals for each customer, and delivers the billing reports torespective of the customers.

[0036] The object storage databases 110 store, organize, and sortinformation for the users of the virtual PBX system 100. The informationstored in the object storage database 1110 includes voice messages,e-mail, faxes, images, documents, and any other information that a userdesires to store and access with the data devices 102 and 104.

[0037] The directory 112 receives queries from the processor 108,accesses the directory database 114, and uses information received fromthe processor 108 to cross reference additional information about usersstored in records and the directory database 114. Information that thedirectory 112 retrieves from the directory database 114 is sent to theprocessor 108. Thus, the directory 112 performs functions such asdetermining the terminal points where a user can be reached, determiningthe user's PBX extension, and/or a network address of a data device.This information is sent to the processor 108 from the directory 112 onthe basis of queries received from the processor 108.

[0038] The directory 112 can also perform all or some of the functionsperformed by the processor 108. Likewise, the processor 112 can performall or some of the functions performed by the directory 112. Thus, it isnot necessary to have both a processor and a directory. As shown in FIG.1, the directory 112 can communicate with the packet-switching network106 and the ACP system 130 as well as the processor 108. As a result,processing can be distributed between the processor 108 and thedirectory 112 in any desired manner.

[0039] The directory database 114 stores records that associate users'aliases with their PBX extensions, group ID numbers, network addresses,and the one or more locations corresponding to each user's PBXextension.

[0040] The traditional telephony network 116 includes one or more PBXs118, telephones 120, a PSTN 122, fax machines 124, modems 126, one ormore packet network telephony gateways 128, and one or more ACP systems130.

[0041] The PBX 118 is any conventional PBX, and the PSTN 122 is anyconventional PSTN. Conventional PBXs and PSTNs are described in Keiserand Strange, “Digital Telephony and Network Integration,” 2^(nd) ed. andin Stallings. “Data and Computer Communications,” 4^(th) ed. Thetelephones 120 are conventional and are connected to and communicatewith, the PBX 118 and the PSTN 122. The fax machines 124 and the modems126 are conventional and are also connected to the PSTN 122.

[0042] The packet network telephony gateway 128 connects thepacket-switching network 106 to the PBX 118 and the PSTN 122. The packetnetwork York telephony gateway 128 receives information from thepacket-switching network 106 and converts the information to a formcompatible with the PBX 118 and/or the PST 122. The packet networktelephony gateway 128 also receives information from the PBX 118 and thePSTN 122 and converts such information into a form compatible with thepacket-switching network 106. Thus, the packet network telephony gateway128 serves as an interface between the packet-switching network 106 ofthe virtual PBX system 100 and the conventional telephony system 116.The packet network telephony gateway 128 may be an H.323 gateway PC,such as that described inhttp://quicknet.net/support/AppNotes/AN0004.htm. The packet networktelephony gateway 128 may include a gatekeeper or other device orsoftware for interfacing a packet-switching network and a conventionaltelephony system.

[0043] The ACP system 130 is any known ACP system for controllingprocesses such as collect call and messaging for example. One such ACPsystem is described in U.S. Pat. No. 5,787,150 to Reiman et al.,entitled “Method and System for Automated Collect Call messaging,” whichis incorporated by, reference herein. The ACP system 130 automaticallyprocesses calls received via the PSTN 122 and connects calls to theprocessor 108 and/or the directory 112 of the virtual PBX-system 100.

[0044] It is emphasized that the virtual PBX system 100 of FIG. 1 is forexemplary purposes only, as many variations and permutations of thehardware used to implement the present invention will be readilyapparent to one having ordinary skill in the art. To implement thesevariations, a single computer (e.g. the computer 1000 of FIG. 10) may beprogrammed to perform the special purpose functions of two or more ofany of the devices shown in FIG. 1. For example, a single computer couldbe programmed to function as both the processor 108 and the directory112. On the other hand, by using distributed processing techniques, forexample, two more programmed computers, may be substituted for any oneof the devices shown in FIG. 1.

[0045] The present invention stores information relating to the users ofthe virtual PBX system 100. This information includes the users' PBXextensions, aliases, IP addresses, and the locations of differentterminal points for each user extension, as well as the order ofpreference that the terminal points are to be accessed or dialed. Thisinformation is stored in one or more memories such as a hard disk,optical disk, magneto-optical disk, and/or random access memory (RAM),for example. One or more databases, such as the storage object database110 and or the directory database 114, may store the information used toimplement the present invention. The databases are organized using datastructures (e.g. records, tables, arrays, fields, and/or lists)contained in a memory such as a hard disk, optical disk, magneto-opticaldisk, and/or RAM, for example.

[0046] FIGS. 2-4 depict data structures for implementing a virtual PBXsystem. These data structures are used by the processor 108 and thedirectory 112 of the virtual PBX system 100 to perform automaticswitching, call routing, and other operations similar to those performedon a conventional PBX. The data structures shown in FIGS. 2-4 are storedin the object storage database 110, the directory database 114, and/orany other suitable storage device. The information stored in the datastructures includes identifiers for uniquely identifying users andlinking users to their PBX extensions, group ID numbers and terminalpoints, as well as for dynamically tracking the network addresses of thedata devices of users that are logged onto the virtual PBX system 100via the IP address of the data devices.

[0047]FIG. 2 shows an extension aliases record 200 that includes a field202 for storing aliases, a field 204 for storing group ID-numbers, and afield 206 for storing users' PBX extensions. An alias is an identifierthat uniquely identifies the user when he or she logs into the virtualPBX system 100. As shown in FIG. 2, the aliases are e-mail addresses.Alternatively, the aliases are any alphanumeric identifiers such as atelephone numbers, social security numbers, billing account numbers,etc. The group ID numbers are associated with respective of the aliasesand identify the group corresponding to each alias. The extensionidentifies the user's virtual PBX extension, which is analogous to anextension in a conventional PBX system. The field 204 for storing thegroup ID numbers does not have to be used. However, the use of group IDnumbers permits users in different groups to have the same PBX extensionnumbers.

[0048]FIG. 3 is an extension locations record 300 that includes a field302 for storing group ID numbers, a field 304 for storing userextensions, a field 306 for storing location orders, and a field 308 forstoring terminal point locations. The group ID numbers and the userextensions are the same as the group identification numbers and theusers extensions stored in the fields 204 and 206, respectively, of theextension aliases record 200. The location order is the order ofpreference that the processor 108 will use in attempting to connectcalls to the terminal point locations associated with a user. Theterminal point locations are stored in field 308. Thus, referring to theextension locations record 300 shown in FIG. 3 by way of example, if theprocessor 108 tries to connect a call to a user with the group ID number299 and the user extension 1234, the processor 108 will first attempt toreach the user via the packet-switching network 106, because the “packetnetwork” entry corresponds to the first terminal point location. Ifattempts to reach the user via the packet-switching network 106 fail,the processor 108 will then try to connect the call to the user via thenumber 555-111-2222, because 555-111-2222 corresponds to the secondterminal point location for the user. Note that 555-111-2222 is aconventional telephone number to be used in the conventional telephonenetwork 116 of FIG. 1, for example. Other examples of locations includevoice mail directories, the receptionist in the building of the user tobe called, the user's secretary, the user's supervisor, and/or a voicemail system.

[0049]FIG. 4 shows a packet network locations record 400 that includes afield 402 for storing group ID numbers, a field 404 for storing userextensions, and a field 406 for dynamically storing the network addressof the user. The group ID numbers and the user extensions are the sameas those stored in the fields 204 and 206, respectively, of theextension aliases record 200 shown in FIG. 2. The network address is theaddress associated with the data devices (e.g., the data devices 102 and104 in FIG. 1) connected to the packet-switching network on which thevirtual PBX system is implemented. In the examples shown in FIG. 4, thenetwork addresses are IP addresses, and thus, the Internet can be usedas the packet-switching network 106. The presence of a network addressin the field 406 corresponding to a particular group ID number in field402 and a particular user extension in the field 404 indicate that theuser associated with that group ID number and user extension number arelogged onto the virtual PBX system (i.e. that user is “online”). Theabsence of an address in the field 406 indicates that the userassociated with the corresponding group ID number in field 402 and thecorresponding user extension in field 404 is not logged into the virtualPBX system 100 (i.e., that user is “offline”).

[0050] Accordingly, when a user logs in, an entry corresponding to theuser's network address (e.g., the IP address of the user's data device)is created in the packet network locations record 300 and associatedwith the user's virtual PBX extension and group ID number. In thismanner, the present invention is able to dynamically track the locationsof users of the virtual PBX system 100 by storing the network address ofthe data device through which the user has logged onto the virtual PBXsystem 100. As an example of the flexibility and convenience that thevirtual PBX 100 of the present invention provides, a user could (1)participate in a telephone conference using the data device 102, whichmay be located in the user's office, (2) disconnect from the conference,and (3) log in using the data device 104, which may be located in theuser's automobile.

[0051] It is to be understood that the data structures shown in FIGS.2-4 are provided by way of example, and many variations and permutationsof the organization of the information used by the present inventionwill be readily apparent to one having ordinary skill in the art. Forexample, a separate record may be used to link users' aliases to theirgroup ID numbers. In that case, separate extension alias records,extension locations records and packet network locations records can becreated for each group and populated only with information for thecorresponding group. Additionally, if each user has a unique userextension number, then the group ID numbers can be eliminated entirely.

[0052]FIG. 5 is a flow chart explaining how a user logs onto the virtualPBX system 100. In step 502 the user connects to the packet-switchingnetwork 106 using a data device, such as the data device 102. Thisconnection can be accomplished using known network protocols. In step504, the agent 103 running on the data device contacts the directory1112 to supply authentication, register the user's alias, and registerthe location of the data device. The authentication, alias, and locationcan be input manually by the user. However, the alias and authenticationare preferably input by the user, and the location (e.g. the IP addressof the data device 102) is sent by the agent 103 to the director 112 viathe packet-switching network 106 automatically. The authentication ispreferably a password that the directory 112 compares to passwordsstored in the directory database 114. If there is a match between theauthentication passwords sent by the agent 103 and one of theauthentication passwords in the directory database 114, then the user isauthenticated (step 506). If there is no match, then the user isdisallowed to the virtual PBX system 100 in step 508.

[0053] If the user successfully logs in, the network address (e.g., theIP address) of the data device that the user has connected to thevirtual PBX system is linked to the virtual PBX extension of the user.As noted above, users are not required to maintain static locations andcan log onto the system on different data devices while maintaining thesame user extension.

[0054]FIG. 6 is a flow chart showing the processing of different optionsavailable to a user logged onto the virtual PBX system 100. The processshown in FIG. 6 is preferably performed by the processor 108, butalternatively; a portion of the processing can be performed by thedirectory 112. In step 602 the processor 108 checks to determine whetherthe user, who is logged into the system, wishes to make an outboundcall. If the user wishes to make an outbound call, then the processproceeds to step 702 shown in FIG. 7. Referring back to FIG. 6, if theuser does not wish to make an outbound call, the processor determineswhether the user wishes to access his or her message options in steps604. If the user wishes to access his or her message options, then theprocess proceeds to step 605 and message options are invoked. Thesemessage options include standard message options available on aconventional telephone network, such as voice mail, message forwarding,reminders, or any other known message options.

[0055] If the user does not wish to access message options in step 604,then the process proceeds to step 606. In step 606, the processor 108determines whether the user wishes to access user options. If the userwishes to access user options, then user options are invoked in step608. User options include standard user options such as storing agreeting message, changing the greeting message, setting the number ofrings before an incoming caller is forwarded to voice mail, or any knownfeatures or options used in a conventional telephony system.Additionally, the user may be permitted to change the location order(stored in the field 306 in FIG. 3) associated with his or her userextension in the extension locations record 300. If the user does notwish to access user options in step 606, then the processor determineswhether the user wishes to disconnect or log oft in step 610. If theuser wishes to disconnect, then in step 612, the data device 102 sends adisconnect message to the directory 112. Then, instep 614, the directoryuses the user's alias, provided at log in, to find the group ID andextension corresponding to the user and locate the user's networkaddress in the packet network locations table 400. Then, the networkaddress is disassociated from the user's group ID number, virtual PBXextension, and alias. As a result the user is logged off and is deemedto be offline.

[0056] If the processor determines in step 6.10 that the user has notdisconnected, then steps 602, 604, 606, and 610 are repeated until theprocessor 108 determines that the user wishes to make an outbound call,access message options, access user options, or disconnect.

[0057]FIGS. 7 and 8 are flow charts for explaining how an outbound callis made. If a user wishes to make an outbound call in step 602 (FIG. 6),then the agent 103 sends a message to the processor 108 to make anoutbound call in step 702. Then, in step 704, the processor 108 queriesthe directory 112 for the destination of the call. In step 706, thedirectory 112 determines whether the destination of the call is aninternal user (i.e. a user of the virtual PBX or a user with an alias).If the destination is not an internal user, then the call is connectedto the PSTN 122 via the packet network telephony gateway 128 in step708. If the destination of the call is an internal user, then thedirectory 112 determines whether the destination is to a PSTN in step802 (FIG. 8) by accessing the first terminal point location for thedestination user in the extensions locations record 300. The locationsstored in the field 308 (FIG. 3) indicate whether the destination user%% ill first be attempted to be contacted on the packet-switchingnetwork 106 or the conventional telephony system

[0058] If the destination is to a PSTN, then the process proceeds tostep 804. In step 804 the directory determines whether the destinationuser is online by determining whether an IP address is associated withthe destination user's virtual PBX extension in the packet networklocations record 400. If an IP address is associated with thedestination user's virtual PBX extension, then the destination user isdetermined to be online. If the destination user is online, then in step806 the directory accesses the packet network locations record 400 tofind the network address of the destination user's data device. Thedestination network address is sent to the processor 108, whichinitiates the call to that network address in step 808. Then, theprocessor 108 determines whether the destination user accepts the callin step 810. If the destination user does not accept the call, then theprocessor 108 notifies the directory 112, and the directory 112determines whether the destination user has more terminal pointlocations in the extension locations record 300 in step 812. If thedestination user has more locations, then the directory 112 selects thenext location, based on the location order in the extension locationstable 300, in step 814, and the process returns to step 704. Similarly,if the destination user is determined to be offline in step 804, thenthe process proceeds to step 812 to determine whether the user hasadditional terminal point locations. If the user has no more terminalpoint locations, then in step 816, the caller is forwarded to thedestination user's voice mail system on the processor 108. Voicemessages are stored in the object storage database 110.

[0059] If, in step 802, the directory 112 determines that thedestination is not to the PST-N 122, then the process proceeds to step818. In step 818 the processor 108 connects the call to the PSTN 122 viathe packet network telephony gateway, 128. Then, in step 820 theprocessor 108 determines whether the call was successful. If the callwas not successful then the process proceeds to step 812 to determinewhether the destination user has more terminal point locations in theextension locations record 300.

[0060]FIG. 9 is a flow chart showing how calls can be made through thePSTN network 122 to the data devices 102 and 104 of the virtual PBXsystem 100. In step 902, a user dials a number corresponding to anotheruser at a data device (e.g., the data device 102) of the virtual PBXsystem. For example, the user at the telephone 120 dials the numbercorresponding to the user at the data device 102. Upon dialing thenumber in step 902, the telephone 120 is connected to the PSTN 122,direction or through the PBX 118, depending on whether the telephone 120is required to access the PSTN 122 through the PBX 118. In step 904, thePSTN 122 determines whether to route the call to the ACP system 130 orto the packet network telephony gateway 128. If the PSTN 122 routes thecall to the ACP system 130, then in step 908, the call is routeddirectly to the processor 108 or alternatively, to the directory 112. Ifthe PSTN 122 routes the call to the packet network telephone gateway128, then in step 906, the call is routed to the processor 108 (oralternatively, the directory 112) via the packet-switching network 106.

[0061] As shown in FIGS. 5-9, call processing and switching within thevirtual PBX system 100 is performed by the processor 108 and directory112, and therefore, the intelligence of the virtual PBX system 100 isadvantageously located on the network side, and not in the terminaldevices (i.e., not within the data devices 102 and 104). Moreover, sincethe call processing and switching is performed by the processor 108 andthe directory 112, there is no need for conventional telephony equipmentfor call routing within the virtual PBX network 100.

[0062] Additionally the interface between the packet network telephonygateway 128 and the virtual PBX system 100 and the ACP system 130provides connection between the virtual PBX system of the presentinvention and existing PSTNs and PBXs.

[0063] All or a portion of the invention may be conveniently implementedusing conventional general purpose computers or microprocessorsprogrammed according to the teachings of the present invention, as willbe apparent to those skilled in the computer art. Appropriate softwarecan be readily prepared by programmers of ordinary skill based on theteachings of the present disclosure, as will be apparent to thoseskilled in the software art.

[0064]FIG. 10 is a schematic illustration of a computer system 1000 forimplementing the method of the present invention. The computer system1000 includes a computer housing 1002 for housing a mother board 1004,which contains a CPU 1006, a memory 1008 (e.g. RAM, dynamic RAM (DRAM),static RAM (SRAM), synchronous DRAM (SDRAM), flash RAM, read-only memory(ROM), programmable ROM (PROM), erasable PROM (EPROM), and electricallyerasable PROM (EEPROM)), and other optional special purpose logicdevices (e.g., application specific integrated circuits (ASICs)) orconfigurable logic devices (e.g., generic array of logic (GAL) orreprogrammable field programmable gate arrays (FPGAs)). The computersystem 1000 also includes plural input devices, such as a keyboard 1022,a mouse 1024, and a microphone 126, and a speaker 128 and display card1010, for controlling a monitor 1020. In addition, the computer system1000 further includes a floppy disk drive 1014; other removable mediadevices (e.g., a compact disc 1019, a tape, and a removablemagneto-optical media); and a hard disk 1012, or other fixed, highdensity media drives, connected using an appropriate device bus (e.g., asmall computer system interface (SCSI) bus, and enhanced integrateddevice electronics (IDE) bus, or an ultra-direct memory access (DMA)bus). The computer system 1000 may additionally include a compact discreader 1018, a compact disc reader-writer unit, or a compact disc jukebox, each of which may be connected to the same device bus or anotherdevice bus. Although the compact disc 1019 is shown in a CD caddy, thecompact disc 1019 can be inserted directly into CD-ROM drives which donot require caddies. In addition, a printer may provide printed listingsof the data structures shown in FIGS. 2-4 or any other data stored andor generated by the computer system 1000.

[0065] As stated above, the system includes at least one computerreadable medium or memory programmed according to the teachings of theinvention and for containing data structures, tables, records, or otherdata described herein. Examples of computer readable media are compactdiscs hard disks, floppy disks, tape, magneto-optical disks. PROMs(EPROM, EEPROM, Flash EPROM), DRAM, SRAM, SDRAM, etc. Stored on any oneor on a combination of computer readable media, the present inventionincludes software for controlling both the hardware of the computer 1000and for enabling the computer 1000 to interact with a human user (e.g.,a consumer). Such software may include, but is not limited to, devicedrivers, operating systems and user applications, such as developmenttools. Such computer readable media further includes the computerprogram product of the present invention for performing all or a portion(if processing is distributed) of the processing performed inimplementing the invention. The computer code devices of the presentinvention can be any interpreted or executable code mechanism, includingbut not limited to scripts, interpreters, dynamic link libraries, Javaclasses, and complete executable programs. Moreover, parts of theprocessing of the present invention may be distributed for betterperformance, reliability, and/or cost.

[0066] The invention may also be implemented by the preparation ofapplication specific integrated circuits or by interconnecting anappropriate network of conventional component circuits, as will bereadily apparent to those skilled in the art.

[0067] Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

1. A method of routing calls within a network, comprising the steps of:receiving from a data device login information including an identifieridentifying a user at the data device and a network address identifyingthe location of the data device on the network; associating a privatebranch exchange extension of the user with the network address;receiving a call to the user's private branch exchange extension; androuting the received call to the data device.